Liner for a flow meter

ABSTRACT

A flow meter assembly includes a flow meter including a tube through which a fluid flows. The flow meter is operable to measure the amount of fluid flowing through the tube. A liner is positioned within the tube and is removably coupled with the tube such that fluid flowing through the tube flows through the liner without contacting an inner surface of the tube.

RELATED APPLICATIONS

This application claims priority to U.S. Provisional Application No.60/677,458 filed May 4, 2005, U.S. Provisional Application No.60/669,594 filed Apr. 8, 2005, U.S. Provisional Application No.60/654,327 filed Feb. 18, 2005, and U.S. Provisional Application No.60/588,242 filed Jul. 15, 2004. The entire contents of these provisionalapplications are hereby incorporated by reference in this application.

FIELD OF THE INVENTION

The invention relates to flow meters.

BACKGROUND OF THE INVENTION

Automated fill systems are used for transferring fluids from a reservoirto containers. Typically, these automated systems incorporate a flowmeter to accurately control the amount of fluid introduced into eachcontainer, either by mass (weight) or volume. These systems aretypically used in the pharmaceutical, biopharmaceutical, chemical, andfood packaging industries. Likewise, the flow meters can also be used inother industries such as water, waste water, paper, energy, andpetrochemical. The automated systems also generally include a stop valvecontrolled by the flow meter and a nozzle used to transfer the measuredamount of fluid to a container.

One type of flow meter commonly used in these automated systems is amass flow meter that measures flow characteristics based on thecontrolled generation of Coriolis forces. This type of mass flow meteris known and generally includes a titanium, stainless steel or otherdurable-material tube that extends centrally through the ends of ahollow enclosed cylinder and that facilitates fluid flow through thecylinder. The enclosed cylinder may contain nitrogen, helium or othersuitable gases. To measure the mass flow rate through the tube, the tubeis oscillated and, based on the actual measured tube oscillations, theflow characteristics can be computed. For example, when there is no massflow through the tube, there is no computed phase difference between theapplied oscillations and the measured oscillations. When there is massflow, the tube oscillations is decreased at the inlet and accelerated atthe outlet. As the mass flow rate increases, the phase difference alsoincreases. The oscillation of the tube is measured using electrodynamicsensors at the inlet and outlet of the tube.

In many industries, such as pharmaceutical and biopharmaceutical, it isimportant to clean, sterilize, and validate permanent (i.e.,non-disposable process piping) conduits within the system to preventcross-contamination when the fluid reservoir is changed to introduce adifferent fluid through the system. This is referred to in the industryas changing batches. When changing batches, it is common to injectcleaning chemicals, pure water, and steam through the conduits to cleanand sterilize them. Conduit portions may also have to be disassembledfor cleaning and sterilization. Because the tube of the mass flow meteris part of the system, it must also be cleaned and sterilized (orreplaced). The cleaning and sterilizing must also be validated prior toproceeding with the next batch. This results in a process that is timeconsuming, labor intensive and costly due to the associated downtime ofthe system.

Typically, systems have added additional valves and fittings at multiplelocations along the conduits of the system to facilitate aclean-in-place (CIP) or steam-in-place (SIP) process and to allowcleaning and validation over smaller sections of the system. Forexample, if the entire system cannot be validated, the contamination canbe isolated to a specific section and then only that specific sectioncan be re-cleaned. In other words, isolation valves allow one or moresections of the flow path to be cut-off to allow for further cleaning ofonly the flow path sections that require cleaning. In this manner,isolation valves could be positioned upstream and downstream of the flowmeter to define the flow meter tube as one isolated flow path. Althoughthis arrangement simplifies cleaning, sterilizing, and validatingbetween batches, it does not eliminate the costly, labor intensive, andtime consuming cleaning process with respect to the flow meter.

Flow meters are also often used in applications that handle andtransport caustic and/or corrosive materials (e.g., sewage treatmentprocesses, chemical production processes, and the like). Over time,these harsh materials can corrode or otherwise degrade the tube in theflow meter, thereby requiring replacement of the flow meter. Suchreplacement is expensive and time consuming.

SUMMARY OF THE INVENTION

The present invention is directed to a disposable liner for a flow meterthat can be replaced to prevent cross-contamination between batches,eliminate the need to clean, sterilize, and validate the tube within theflow meter, increase productivity of the filling system by decreasingsystem downtime, and reduce labor and other costs associated with theotherwise necessary cleaning and validation process. In addition, thedisposable liner of the invention can be used to substantially reduce oreliminate corrosion or degradation of the flow tube in flow meters usedin applications handling caustic and/or corrosive materials. Liners canbe inserted and replaced as necessary to protect the integrity of theexpensive flow tube.

One embodiment of the present invention is directed to a filling systemincluding a fluid reservoir and a flow meter fluidly coupled together.The fluid reservoir supplies fluid to the flow meter and the flow metermeasures flow characteristics. The flow meter also includes a tubeassociated with measuring the flow characteristics and a removableinsert or liner positioned within the tube adapted to contain andtransfer the fluid from the reservoir and through the flow meter.

In other embodiments, the filling system includes a stop valve and anozzle fluidly coupled together with the flow meter. The flow metercontrols the stop valve thereby allowing the nozzle to introduce only ameasured amount of fluid to a container.

In some embodiments, the flow meter is a mass flow meter that measuresflow characteristics based on the controlled generation of Coriolisforces. This tube of the mass flow meter extends centrally through theends of a hollow enclosed cylinder. At least one electrodynamic sensoris positioned within the cylinder to measure flow characteristics basedon the generation of Coriolis forces.

In other embodiments, the present invention contemplates the use of aremovable, un-bonded liner in other types of flow meters (e.g.,electromagnetic type flow meters). A removable liner used in other typesof flow meters can also be inserted into and removed from the flow meterby itself apart from any supporting structure, thereby allowing the flowmeter to operate either with or without the liner.

In yet other embodiments of the invention, the insert is a flexibletube. The flexible tube can be a non-reactive, pre-irradiated, plasticflexible tubing. The insert is inserted within the tube of the flowmeter such that the outer surface of the insert substantially contactsthe inside surface of the tube.

In yet further embodiments of the invention, the insert is a removable,formed or formable liner that can be shaped to conform to the innersurface of the tube in the flow meter, regardless of the size andconfiguration of the tube.

Other features and advantages of the invention will become apparent tothose skilled in the art upon review of the following detaileddescription, claims, and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic view of the filling system according to oneembodiment of the present invention.

FIG. 2 is a perspective view of a flow meter of the filling system ofFIG. 1.

FIG. 3 is a plan view of a first liner embodiment for use in the fillingsystem of FIG. 1.

FIG. 4 is an exploded view of a filling system illustrating thecomponents used for installing a second embodiment of a liner.

FIG. 5 illustrates the filling system of FIG. 4 in a partially assembledstate.

FIG. 6 is an enlarged perspective view showing the insert fixtures ofthe filling system of FIG. 4.

FIG. 7 is a bottom view of the insert fixtures of FIG. 6.

FIG. 8 is a partial perspective view showing the liner being secured inplace over the upper insert fixture.

FIG. 9 is a partial perspective view showing the liner being secured inplace over the lower insert fixture.

FIG. 10 is an exploded partial perspective view showing the connectionbetween the inlet line of the filling system and the upper insertfixture.

FIG. 11 is schematic view illustrating the air purge pathways for thefilling system of FIG. 4.

FIG. 12 is an exploded partial perspective view illustrating a vacuumport assembly embodiment for use with the filling system.

FIG. 13 is a partial perspective view showing the vacuum port assemblyof FIG. 12 fully assembled.

FIG. 14 is a partial perspective view showing a second vacuum portassembly assembled with the filling system.

FIG. 15 is a plan view of a fill line incorporating the liner of FIG. 3.

FIG. 16 is a section view of a filling system incorporating a disposablefill line that is a third embodiment of a liner.

FIG. 17 is an exploded view of the filling system of FIG. 16.

FIG. 18 is a plan view, partially in section, of the disposable fillline shown in FIGS. 16 and 17.

FIG. 19 is a partial perspective view of the upper end cap fixturesecured to the flow meter.

FIG. 20 is a partial perspective view of the lower end cap fixturesecured to the flow meter.

FIG. 21 is a view similar to FIG. 19 illustrating the connection of thedisposable fill line to the upper end cap fixture.

FIG. 22 is a view similar to FIG. 20 illustrating the connection of thedisposable fill line to the lower end cap fixture.

FIG. 23 is schematic view illustrating the air purge pathways for thefilling system of FIG. 16.

FIG. 24 a is a plan view of a hairpin clip used to connect thedisposable fill line to the upper and lower end cap fixtures.

FIG. 24 b is a plan view of an alternative end cap fixture and C-cliparrangement operable to secure the disposable fill line in position withrespect to the flow meter.

Before one embodiment of the invention is explained in detail, it is tobe understood that the invention is not limited in its application tothe details of construction and the arrangements of the components setforth in the following description or illustrated in the drawings. Theinvention is capable of other embodiments and of being practiced orbeing carried out in various ways. Also, it is understood that thephraseology and terminology used herein is for the purpose ofdescription and should not be regarded as limiting. The use of“including”, “having” and “comprising” and variations thereof herein ismeant to encompass the items listed thereafter and equivalents thereofas well as additional items. The use of letters to identify elements ofa method or process is simply for identification and is not meant toindicate that the elements should be performed in a particular order.

DETAILED DESCRIPTION

A filling system 10 according to one embodiment of the present inventionis illustrated in FIG. 1. The filling system 10 includes a fluidreservoir 12, a flow meter 14, a stop valve 16, and a nozzle 18 fluidlycoupled together. The fluid reservoir 12 is a container that holds afluid. The fluid reservoir 12 can be a tank, a bag, a tub, or any vesselcapable of holding a fluid. As used herein and in any appended claims,the term “fluid” is intended to include liquids, gases, and any otherflowable solids or media capable of flowing or being passed through aflow meter (e.g., slurries, sludges, granular materials, sewage, heavycreams, pastes, and the like). The fluid in the reservoir 12 flows outof the reservoir 12 due to pressure applied within the reservoir 12. Inother constructions, the system 10 could include a pump, such as aperistaltic pump, to move the fluid from the reservoir 12 and throughthe system 10. The filling system 10 can be used in pharmaceutical,biopharmaceutical, chemical, food packaging, and other industries.Likewise, the present invention contemplates use in flow meters used inother industries such as water, waste water, paper, energy, paint,cosmetic and petrochemical where the materials passing through the flowmeters may be caustic and/or corrosive.

The flow meter 14 is fluidly coupled to the fluid reservoir 12 byconduit 20 a. The flow meter 14 includes an enclosed hollow cylinder 22and a centrally located tube 24 that extends through the ends of thecylinder 22 to define a passageway. The cylinder can contain nitrogen,helium or other gases to facilitate operation of the flow meter 14. Aninsert, liner, or conduit 20 b is positioned within the passageway ofthe tube 24 and fluidly connects to the conduit 20 a to selectivelyreceive fluid from the fluid reservoir 12. The flow meter 14 alsoincludes first and second electrodynamic sensors 26 a, 26 b thatgenerate and send signals representative of the oscillations of the tube24. In the illustrated embodiment, the flow meter 14 is a Coriolis flowmeter such as a Coriolis flow meter available from Micro Motion,Endress+Hauser and others. The operation of a Coriolis flow measuringsystem is understood to one of ordinary skill in the art and istherefore not presented in detail in this application. In otherembodiments, other flow measuring systems which include a tube for fluidtransfer can also be used.

The conduit 20 b can be a flexible, semi-rigid, or rigid plastic tubing.For example, the tubing can be made of polyethylene, polypropylene,polyolefins, nylon, thermoplastic elastomer, or any combination of thesematerials. Other formable materials that are resistant to corrosivefluids can also be used. In some embodiments, the outside wall of theconduit 20 b substantially contacts a substantial portion of the entireinterior surface of the tube 24. Making solid contact with the walls ofthe tube 24 allows a more accurate measurement to be taken by thesensors 26 a, 26 b as the fluid flows through the conduit 20 b. Theconduit 20 b is capable of being sterilized prior to insertion into thepassageway of the tube 24. In some embodiments, the conduit 20 b can beirradiated, washed, chemically sterilized, or the like. In yet otherembodiments, the conduit 20 b is pre-sterilized and packaged to maintainsterility. The conduit 20 b can be held within the tube 24 by frictionalengagement between the tube 24 and the conduit 20 b, or throughmechanical fasteners such as clamps, screws, pressure, etc.

While the illustrated shape of the conduit 20 b is an elongated tube,the conduit 20 b could take on various other shapes (i.e., a formed orformable liner to accommodate substantially any tube configuration) thatallow connection with conduits 20 a, 20 c and insertion into the tube24. For example, there are numerous flow meter units that utilizedifferent tube configurations. Multi-tube flow meters, and flow metershaving curved and/or branched tubes are available. The present inventioncontemplates flexible, semi-rigid, and rigid liner configurationsconfigured to work with substantially any flow meter tube configurationsand constructions. The present invention also contemplates the use of aremovable, un-bonded liner in other types of flow meters (e.g.,electromagnetic type flow meters). As with the conduit 20 b, a removableliner used in other types of flow meters can also be inserted into andremoved from the flow meter by itself apart from any supportingstructure, thereby allowing the flow meter to operate either with orwithout the liner.

FIG. 3 illustrates one embodiment of the conduit 20 b in more detail.The illustrated conduit 20 b of FIG. 3 includes a first portion 50, asecond portion 54, and a third portion 58. The sizes and lengths of theportions 50, 54, and 58 will vary depending on the specific flow meterused, however, the second portion 54 is sized to fit within the tube 24.More specifically, the second portion 54 has an outside diameter that issubstantially the same as or slightly larger than the inside diameter ofthe tube 24. This enables the outer surface of the second portion 54 tomaintain contact with the inner surface of the tube 24 alongsubstantially the entire length of the tube 24. In other embodiments, aswill be discussed below, the outside diameter of the second portion 54can be slightly smaller than the inside diameter of the tube 24. Thesecond portion 54 has a low durometer value and a thin wall thickness soas to closely conform to and abut the inner surface of the tube 24.

The illustrated first and third portions 50, 58 are coupled to oppositeends of the second portion 54. The first and third portions 50, 58extend out of the tube 24 and have a higher durometer value and greaterwall thickness than the second portion 54 to accommodate the flow ofpressurized fluid where there is no rigid structure surrounding the tube24 (e.g., above and below the upper and lower ends of the tube 24 andcylinder 22 as shown in FIG. 1). As used herein and in any appendedclaims, the terms “up”, “down”, “upper”, “lower”, “above”, “below”, andthe like are for the purposes of facilitating the description in lightof the figures, and are not intended to imply or require any particularorientation of parts. If desired, the first and third portions 50, 58can be reinforced with a braided or meshed material, or a removablesolid fitment or fixture can be used at the ends of the cylinder 22 tohelp stabilize the first and third portions 50, 58. The illustratedconduit portions 50, 54, and 58 are made of commercially availablethermoplastic elastomer C-FLEX medical grade tubing available fromConsolidated Polymer Technologies, Inc. of Clearwater Fla., however,other suitable tubing, conduit, liner, and film materials can also beused. C-FLEX tubing is known for its bio-compatibility, temperaturestability, moisture stability, sterile compatibility, and is madewithout toxic plasticizers, making it a good choice for pharmaceutical,chemical, and food packaging applications.

In the illustrated embodiment, one end of the first portion 50 isinserted into an end of the second portion 54, and the portions 50, 54are coupled together to form a substantially leak-proof connection. Asimilar connection is formed between the second portion 54 and the thirdportion 58. In the illustrated embodiment, the portions 50, 54 and 54,58 can be thermally bonded together using a length of shrink wrap orshrink tubing 62 positioned over the joints between the portions 50, 54,58. Heat can be applied to the shrink tubing 62 using a heat gun orother suitable heat-emitting device to shrink the shrink tubing 62 forthermal bonding. Of course, other suitable joining techniques, such asfuse welding, RF welding, overmolding and the like can be used to jointhe portions 50, 54, 58 together. Alternatively, the portions 50, 54, 58could be integrally extruded as one length of variable diameter,variable wall thickness, and variable durometer value conduit.

The conduit 20 b is fluidly coupled to the stop valve 16 by conduit 20c. The stop valve 16 can include an actuator 28 that receives signalsand is actuable to pinch the conduit 20 c to restrict fluid flow throughthe conduit 20 c. The actuator can be a pneumatic or hydraulicpiston/cylinder assembly. Other valves for restricting the flow throughthe conduit 20 c can also be used and are within the scope of thepresent invention.

The conduit 20 c is fluidly coupled to the nozzle 18 by conduit 20 d.The nozzle 18 directs fluid flow from the conduit 20 d and into acontainer 30 such as bags, bottles, ampoules, and the like.

The conduits 20 a, 20 b, 20 c, 20 d define a flow path and can becoupled together by couplings 32 known to those of ordinary skill in theart. The flow path need not be separate conduits 20 a, 20 b, 20 c, 20 dcoupled together by couplings, but instead can include a single integralconduit or any number of conduits coupled together to form the flow pathof the filling system. For example, the conduit 20 a, 20 b can beintegrally formed such that a single conduit extends from the fluidreservoir 12 through the flow meter 14. Likewise, the conduits 20 c, 20d can be integrally formed such that a single conduit extends from theflow meter, through the valve stop, and to the nozzle. Any combinationof adjacent conduits 20 a, 20 b, 20 c, 20 d can be integrally formed toform the flow path and reduce the number of separately-coupled conduits.One example of an entirely disposable fill line assembly thatincorporates the conduits 20 a, 20 b, 20 c, 20 d and other components ofthe filling system 10 will be described below with respect to FIG. 4.

The filling system 10 also includes a controller 34 that includes aninput electrically coupled to the first and second sensors 26 a, 26 b bywires 36 a, 36 b, respectively, to receive the signals from the sensors26 a, 26 b, and an output that is electrically coupled to the stop valve16 by wire 38 to send signals to the actuator 28. The controller 34 caninclude a keypad allowing an operator to input a parameterrepresentative of a desired volume of fluid to be filled into eachcontainer 30.

Initially, prior to operation, the filling system 10 includes the fluidreservoir 12 and conduit 20 a fluidly coupled together and the conduit20 c, stop valve 16, conduit 20 d, and nozzle 18 fluidly coupledtogether. To prepare the flow meter 14 to be connected to the system,conduit 20 b is inserted into the passageway of the tube 24. In somecases, it is desirable to have the exterior surface of the conduit 20 bin contact with the interior surface of the tube 24. In order to insertthe conduit 20 b in this instance, the conduit 24 is stretched to reducethe outside diameter of the conduit 20 b thereby allowing clearance forthe conduit 20 b to fit within the passageway of the tube 24. After theconduit 20 b is inserted, some or all of the axial tension force can beremoved from the conduit 20 b such that the outside diameter of theconduit 20 b returns to normal or closer to normal to frictionallyengage the interior wall of the tube 24. If the outer diameter of theconduit 20 b is substantially the same as or slightly larger than theinner diameter of the tube 24, the conduit 20 b can remain under sometension to retain a slightly smaller outer diameter than the inner wallof the tube 24. Then, the pressurized fluid passing through the conduit20 b can expand the conduit 20 b into engagement with the inner wall ofthe tube 24. In other embodiments, the conduit 20 b can be cooled toshrink the diameter for insertion and allowed return to ambienttemperature allowing the diameter to enlarge back to normal within thepassageway of the tube 24. In yet other embodiments, the conduit 20 bcould be initially in a collapsed state for insertion into the tube 24.Once inserted, the conduit could be inflated or expanded using a gas,the liquid from the filling system 10, or other suitable means.

One method of installing the conduit 20 b will now be described withrespect to the conduit 20 b illustrated in FIG. 3. First, one of thefirst or third portions 50, 58 is inserted into the upper end of thetube 24 and fed through the tube 24 until the second portion 54 isproperly positioned within the tube 24. In the illustrated embodiment,the second portion 54 is properly positioned within the tube 24 when theinterface 66 between the first and second portions 50, 54 is generallyaligned with a weld point 70 (see FIG. 1) where the tube 24 is weldedinto the hollow cylinder 22. Likewise, the interface 74 between thesecond and third portions 54, 58 will be generally aligned with a weldpoint 78 where the tube 24 is welded into the hollow cylinder 22. It isbelieved that this alignment technique substantially prevents theconduit 20 b from altering or hindering the oscillation of the tube 24in a non-linear manner, which could impact the accuracy of the flowmeter readings. Instead, with the conduit 20 b properly positionedwithin the tube 24, the effect of the conduit 20 b on the oscillation oftube 24 becomes substantially linear. As a result, a simple calibrationmay be performed to account for the presence of the conduit 20 b withinthe tube 24. In addition to the methods described above for facilitatinginserting the conduit 20 b into the tube, a friction-reducing agent(e.g., a powder, lubricants, alcohol, and the like) can be applied tothe outer surface of the conduit 20 b to facilitate insertion into thetube 24.

Indicia 82 a, 82 b in the form of markings, notches, ribs, detents,bumps, and the like can be provided on the first and third portions 50,58, respectively, to facilitate installation of the conduit 20 b.Specifically, the indicia 82 a, 82 b can be positioned on the conduit 20b to indicate to the installer how far to pull the conduit 20 b throughthe tube 24. For example, the indicia 82 a, 82 b can be located on thefirst and third portions 50, 58 so that when the indicia 82 a alignswith a fixed point 86 (see FIG. 1) on the cylinder 22 and/or tube 24 andthe indicia 82 b aligns with a fixed point 90 (see FIG. 1) on thecylinder 22 and/or tube 24, the conduit 20 b is properly positionedwithin the tube 24. If the indicia 82 a, 82 b take the form of ribs orbumps, the ribs or bumps can act as stops that fit against and/or engagethe fixed points 86, 90. Of course, the fixed points 86 and 90 and thelocations of the indicia 82 a, 82 b could vary. For example, the fixedpoints could alternatively be at clamps, fitments, fixtures, or otherfixed structure adjacent the ends of the cylinder 22, and the indiciacould be positioned at the appropriate corresponding location on theconduit.

When the conduit 20 b is properly inserted within the tube 24, theconduit 20 b can be connected to the conduits 20 a, 20 c. In otherconstructions, the conduit 20 b can be connected to or integrally formedwith one or more of the other conduits 20 a, 20 c, 20 d prior toinsertion into the tube 24, as discussed below with respect to FIG. 4.

After the system 10 is fully assembled, operation of the system 10begins with the stop valve 16 pinching the conduit 20 c such that thefluid flow through the flow path is restricted. A container 30 ispositioned in operational relationship with the nozzle 18 such thatfluid exiting the nozzle 18 enters the container 30. After the container30 is properly positioned, the controller 34 sends a signal to theactuator 28 to move out of contact with the conduit 20 c such that fluidfrom the reservoir 12 is allowed to flow through conduits 20 a, 20 b, 20c, and 20 d, out the nozzle 18, and into the container 30. Due to thepresence of the conduit 20 b, the fluid does not contact the innersurface of the tube 24.

As the flow of fluid begins through the flow path, the sensors 26 a, 26b generate and send signals representative of the oscillations of thetube 24. The controller 34 receives the signals from the sensors 26 a,26 b and calculates the amount of fluid that flows through the flowmeter 14 based, at least partially, on the received signals and theCoriolis principle. When the controller 34 identifies that the desired,preprogrammed amount of fluid has moved through the flow meter 14, thecontroller 34 sends a signal to the actuator 28 of the stop valve 16.The actuator 28 will pinch the conduit 20 c closed in response toreceiving the signal from the controller 34.

After the stop valve 16 is closed and the container 30 is filled to thedesired volume, the container 30 can be capped or sealed and removedfrom the system 10. The next container is then introduced into thesystem 10 to replace the filled container 30 and the process of fillingthe container repeats itself until the reservoir 12 is emptied or adesired number of containers have been filled.

At such time, a new batch begins by replacing the reservoir 12 with anew reservoir containing a new fluid. Rather than clean, sterilize, andvalidate the tube 24 of the flow meter 14 (as discussed in theBackground), the conduit 20 b can be replaced. To replace the conduit 20b, the conduit 20 b is disconnected from the conduits 20 a, 20 c. Theused conduit 20 b is then removed from the tube 24 by pulling it throughthe tube 24. In most cases, the flow meter 14 need not be disassembledto remove the tube 24 from the flow meter 14 in order to remove theconduit 20 b. The end of the conduit 20 b can be capped to prevent anyfluid from spilling into the tube 24 as the conduit 20 b is being pulledthrough the tube 24. A new sterilized conduit similar to conduit 20 b ispositioned within the passageway of the tube 24 in the manner describedabove. As with removing the conduit 20 b, in most cases, the flow meter14 need not be disassembled to remove the tube 24 from the flow meter 14in order to insert the new conduit 20 b. When the new conduit isinserted, the new conduit is connected to the conduits 20 a, 20 c, whichhave either been replaced by corresponding sterile conduits or cleaned,sterilized, and validated.

After the conduit 20 b is removed from the tube 24, it is intended to bediscarded. In some non-sterile applications, a disposable liner may beindividually cleaned, sterilized, validated and reused until its usefullife has expired. For example, if the conduit 20 b is a piece offlexible plastic tubing, the cost is minimal and therefore it can bediscarded or recycled and replaced with a new pre-sterilized conduit. Inapplications in which caustic and/or corrosive materials are run througha flow meter, the conduit 20 b can be used to protect the tube 24 of theflow meter. In such cases, the conduit 20 b acts as a protective anddisposable liner that after time may degrade due to the contact with thecaustic and/or corrosive chemicals. However, the conduit can be replacedas needed to preserve the integrity of the more expensive tube 24 insidethe flow meter. Using the disposable conduit 20 b as a liner for thetube 24 may eliminate the need for periodic disassembly of the flowmeter 14 in order to replace an unprotected, non-sterile or damaged tube24, or possibly the need for completely replacing the flow meter 14 ifan unprotected tube 24 is damaged. In addition, the use of thedisposable conduit 20 b is not a permanent alteration to the flow meter14 and does not alter the functionality of the flow meter 14 if the flowmeter 14 is later used without the conduit 20 b. With this invention theflow meter tube 24 remains unchanged and will function with or withoutthe liner, but may need recalibration.

Another embodiment of the conduit 20 b and a method of installing theconduit 20 b into the flow meter 14 will now be described with referenceto FIGS. 4-11. In this embodiment, the conduit 20 b is made from asingle piece of C-FLEX medical grade tubing. While various durometervalues of the C-FLEX tubing can be used (e.g., tubing with durometervalues ranging from 18-70 on the A scale), it has been found that alength of C-FLEX tubing with a durometer value of 50 on the A scaleprovides accurate results. Additionally, the illustrated tubing has anoutside diameter that is the same as or preferably smaller than theinner diameter of the tube 24.

First, an appropriate length of the C-FLEX tubing is provided (e.g., cutto length) to form the conduit 20 b to fit within the tube 24. Thespecific length of the conduit 20 b will vary depending on the flowmeter 14 being used. The outer surface of the conduit 20 b can be coatedwith a lubricant or material that will reduce friction and adhesion whenthe conduit 20 b is inserted into the tube 24. In the illustratedembodiment, the conduit 20 b can be rolled in or otherwise coated withsuitable sterile and/or non-toxic medical grade lubricants, talcumpowder, greases, sprays, or similar products that will reduce frictionand adhesion. Any excess lubricant or friction reducing material can beremoved from the conduit 20 b prior to installation.

Next, one end of the conduit 20 b can be secured to a rod or otherelongated member that can be used to insert and pull the conduit 20 bthrough the tube 24 of the flow meter 14. For example, one end of theconduit 20 b can be taped or otherwise coupled to the rod. However,other means for securing the conduit 20 b to the rod can also be used.Any suitable device and method for inserting the conduit 20 b into thetube 24 can be employed, and care should be taken not to damage the tube24.

Prior to inserting the conduit 20 b into the tube 24, the tube 24 can becleaned with a brush, a soft cloth, or other suitable cleaning device.Alternatively or additionally, pressurized air could also be blownthrough the tube 24 for cleaning purposes. In one embodiment, a papercloth can be attached to an elongated rod that is pulled through thetube 24 to clean the tube 24.

Next, insert fixtures 150 a, 150 b for the flow meter 14 are placed intothe respective openings at the top and bottom of the cylinder 22 of theflow meter 14 (see FIG. 5). In the illustrated embodiment, the fixtures150 a, 150 b are inserted until a flange 155 a, 155 b on the respectivefixture 150 a, 150 b abuts a flange 160 a, 160 b or abutment surface onthe end of the cylinder 22. The fixtures 150 a, 150 b are then securedin place using a clamp 165 or other suitable securing device. In theillustrated embodiment, conventional sanitary clamps 165 a, 165 b aresecured at both ends of the cylinder 22 to couple the flange 155 a, 155b on the insert fixture 150 a, 150 b and the flange 160 a, 160 b on therespective end of the cylinder 22 together. In other embodiments, theinsert fixtures 150 a, 150 b may be permanently secured to or integrallyformed with the cylinder 22 of the flow meter 14.

FIGS. 6 and 7 further illustrate the insert fixtures 150 a, 150 b, whichin the illustrated embodiment are substantially identical. The tubularbody portion of the insert fixtures 150 a, 150 b have an outer diameterthat is smaller than the inner diameter of the tube 24, therebyproviding an annular gap between the tubular body portion of the insertfixture 150 a, 150 b and the inner wall of the tube 24. This gapprevents the fixtures 150 a, 150 b from contacting the tube 24, therebyisolating the fixtures 150 a, 150 b from the tube to ensure that thefixtures 150 a, 150 b do not substantially alter the excitationfrequency of the tube 24. Isolating the fixtures 150 a, 150 b from thetube 24 helps to achieve accurate and repeatable measuring results.While the length of the fixtures 150 a, 150 b can vary depending on theflow meter 14, the fixtures 150 a, 150 b should stop short of reachingthe sensors 26 a, 26 b when inserted into the tube 24.

The fixtures 150 a, 150 b also facilitate the repeatability ofinstalling the conduit 20 b into the tube 24. Using the fixtures 150 a,150 b helps ensure that every time a new conduit 20 b is installed, theconduit 20 b will contact the inner wall of the tube 24 at substantiallythe same location. This helps to achieve accurate and repeatable resultsfor the flow meter 14.

The illustrated fixtures 150 a, 150 b are made of a metal such asstainless steel. However, other alloys or disposable plastics could alsobe used for the fixtures 150 a, 150 b. If the fixtures 150 a, 150 b aremade from a disposable plastic material, the fixtures 150 a, 150 b couldbe part of a disposable fill line system like that shown and describedbelow with respect to FIGS. 15 and 18 for single use aseptic or sterileapplications.

With the fixtures 150 a, 150 b inserted, the conduit 20 b can beinserted into the tube 24 using the elongated rod or other installationdevice. In the illustrated embodiment, the rod is inserted into theopening in the upper insert fixture 150 a, passed through the tube 24,and exits the cylinder through the opening in the lower insert fixture150 b. Of course, the rod could also be inserted into the opening in thelower insert fixture 150 b first, passed through the tube 24 in anupward direction, and then exit the cylinder 22 through the opening inthe upper insert fixture 150 a. The free or unsecured end of the conduit20 b is then wrapped over a second flange 156 a of the upper insertfixture 150 a to secure the upper end of the conduit 20 b to the upperinsert fixture 150 a (shown schematically in FIG. 8). Next, the rod ispulled through the tube 24 until the end of the conduit 20 b that issecured to the rod appears from the opening in the lower insert fixture150 b. The conduit 20 b will be slightly stretched (i.e., under slighttension) at this point, and will remain slightly stretched wheninstalled. While firmly grasping the end of the conduit 20 b, the tapeor other securing means can be removed so that the rod can be removedfrom the conduit 20 b and completely withdrawn from the cylinder 22. Thelower end of the conduit 20 b is then wrapped over a second flange 156 bof the lower insert fixture 150 b to secure the lower end of the conduit20 b to the lower insert fixture 150 b (shown schematically in FIG. 9).

Now that the conduit 20 b is positioned in the tube 24, the appropriatelines can be connected to the upper and lower insert fixtures 150 a, 150b. First, a gasket 170 can be placed on the flange 156 a of the upper(and in this case “inlet”) insert fixture 150 a (see FIG. 10). Next, thefluid supply line or conduit 20 a is connected to the inlet insertfixture 150 a using a conventional sanitary clamp 175 a or othersuitable connector. The same operations are then repeated to connect theoutlet line or conduit 20 c and/or 20 d to the lower or “outlet” insertfixture 150 b.

Next, the fluid supply to the flow meter 14 is turned on to supplypressurized fluid to the conduits 20 a, 20 b, and 20 c/20 d. Thepressurized fluid passing through the conduit 20 b begins to expandand/or form the conduit 20 b to the inner wall of the tube 24. Fluidsand gases (e.g., air) that are trapped between the conduit 20 b and thetube 24 begin to be purged from the system 10 as the conduit 20 bexpands and conforms to the shape of the inner wall of the tube 24. Morespecifically, and with reference to FIG. 11, the gap between the outerdiameter of the fixtures 150 a, 150 b and the inner diameter of the tube24 provides a pathway for air trapped between the conduit 20 b and thetube 24 to be purged. Air can travel between the tubular body portionsof the fixtures 150 a, 150 b and the inner wall of the tube 24 towardthe flanges 155 a, 155 b (as generally represented by the flow lines Ain FIG. 11). Referring again to FIG. 7, the flanges 155 a, 155 b arecoupled to the tubular body portion of the respective fixtures 150 a,150 b in a manner that provides one or more air gaps for the air toescape. As shown in FIG. 7, the flanges 155 a, 155 b are welded to thebody portion of the fixtures 150 a, 150 b in four places W, leaving fourarcuate gaps between the flanges 155 a, 155 b and the tubular bodyportions of the fixtures 150 a, 150 b through which air can escape. Ofcourse, fewer or more welds W can be used.

Air is also purged from inside the fluid supply line or conduit 20 a,the conduit 20 b, and the conduit 20 c/20 d by running fluid through theconduits 20 a, 20 b, and 20 c/20 d for at least about three seconds.

Once the excitation current of the flow meter 14 stabilizes, thepressure in the fluid supply line or conduit 20 a is increased tofurther expand and form the conduit 20 b to the inner wall of the tube24. After some time has passed, the conduit 20 b will completely conformto the inner wall of the tube 24 so that substantially no air is trappedbetween the inner wall of the tube 24 and the conduit 20 b. Because theconduit 20 b will have expanded against the inner wall of the tube 24,there should not be any wrinkles, folds, or other irregularities in theconduit 20 b. Any air that was trapped between the inner wall of thetube 24 and the conduit 20 b will have been completely purged andevacuated, and will have exited the system 10 in the manner describedabove, thereby enabling the flow meter 14 with the removable conduit 20b to provide accurate and repeatable measurements.

As an alternative, or in addition to air purging steps discussed above,a vacuum port could be attached to one or both of the insert fixtures150 a, 150 b or otherwise integrally formed with the flow meter 14 andcould be used to evacuate the air between the conduit 20 b and the tube24. FIGS. 12 and 13 illustrate one possible assembly 179 that includes avacuum port 180 a that facilitates the evacuation of the space betweenthe conduit 20 b and the tube 24. As illustrated in FIG. 12 the assembly179 includes an insertion fixture 185 that includes a flange 190 at oneend and a collar 195 between the first end and a second end. The flange190 is similar to the flanges 156 a, 156 b described above and will notbe described in detail. The collar 195 is a substantially disk-shapedportion that is formed as part of the insertion fixture 185 or isfixedly attached (e.g., welded, glued, soldered, brazed, etc.) to theinsertion fixture 185. A spool 200 includes an upper spool flange 205, alower spool flange 210, and an internal aperture that allows the spool200 to slide freely over the insertion fixture 185. The vacuum port 180a extends from the outer surface of the spool to the internal apertureto provide fluid communication therebetween. A hose fitting 220, such asa threaded compression fitting, engages the vacuum port 180 a andprovides for the connection of a vacuum conduit 225 that extends fromthe hose fitting 220 to a vacuum source, such as a vacuum pump.

The insertion fixture 185, with the spool 200 positioned as illustratedin FIGS. 12 and 13, fits within a top opening in the flow meter 14 suchthat the insertion fixture 185 enters the flow meter 14, and in someconstructions enters the tube 24. The lower spool flange 210 slides intoa mating position relative to the cylinder flange 160 a. In someconstructions, a gasket, o-ring, or other resilient member 230 ispositioned between the flange 160 a and the lower spool flange 210 toassure a substantially air-tight seal. A clamp 235, shown in FIG. 13,engages the flange 160 a and the lower spool flange 210 and retains themin a sealed position. Once the clamp 235 is engaged, a vacuum flow pathextends from the exterior of the spool 200 to the interior of the spool200, along the outer surface of the insertion fixture 185 to theinterior surface of the tube 24. With the liner 20 b positioned aspreviously described, the vacuum path extends into the space between theliner 20 b and the tube 24.

The collar 195, shown in FIG. 12, slides into an engagement positionwith the upper spool flange 205. As illustrated in FIG. 12, a resilientmember 237 such as a gasket, o-ring, or other sealing device can bepositioned between the upper spool flange 205 and the collar 195 toprovide a substantially air-tight seal. An upper clamp 240 (shown inFIG. 13) engages the upper spool flange 205 and the collar 195 andcompresses the sealing device 237 to establish a substantially air-tightseal. Thus, the vacuum path is sealed from the atmosphere and extendsinto the space between the tube 24 and the liner 20 b such that thevacuum source is able to draw gas (e.g., air) from the space between thetube 24 and the liner 20 b.

The liner 20 b extends out the top of the insertion fixture 185 andengages the flange 190 as was described with regard to FIG. 8 above. Thegasket 170 can be positioned on top of the liner 20 b and the flange 190as shown in FIG. 10. The liquid supply line 20 a is then positioned ontop of the gasket 170 and a supply clamp 175 a is positioned to sealablycouple the liquid supply line 20 a to the liner 20 b and the flange 190of the insertion fixture 185, as illustrated in FIG. 13.

FIG. 14 illustrates a vacuum assembly 245 similar to the assembly 179described with regard to FIGS. 12 and 13. However, the vacuum assembly245 of FIG. 14 attaches to the outlet end of the flow meter 14 ratherthan to the inlet end. The outlet conduit 20 c attaches to the vacuumassembly 245 using a clamp 175 b that is similar to the clamp 175 a andin a manner similar to that described above. Some constructions mayinclude an inlet vacuum assembly 179, an outlet vacuum assembly 245, orboth, as may be required by the particular application. Additionally,other purging devices or assemblies can be also be used.

Once the air has been evacuated from between the conduit 20 b and thetube 24, the pressure in the supply line or conduit 20 a can be adjustedto the desired filling pressure and batching of the fluid can begin.While two methods of venting or evacuating the air from between theconduit 20 b and the tube 24 have been described above in detail withrespect to the fixtures 150 a, 150 b and 185, it should be noted thatother techniques for purging the air can also be used to achieve theaccurate and repeatable results desired when using the replaceableconduit or liner 20 b.

FIG. 15 illustrates one example of a disposable fill line assembly 100that incorporates the conduits 20 a, 20 b, 20 c, and 20 d into a singleassembly. The fill line assembly 100 can also include other componentsof the filling system 10, such as the nozzle 18. In addition, the fillline assembly 100 can be configured to accept an aseptic filter 104 orother device that might be useful depending on the particular fillsystem application.

The fill line assembly 100 includes a first portion 108 corresponding tothe conduit 20 a shown in FIG. 1. A removable cap 112 can be placed onthe end of the first portion 108 until the first portion 108 is to becoupled to the reservoir 12. The length of the first portion 108 can bevaried as desired depending on the specific filling system used. Asecond end of the first portion 108 is illustrated as being connectableto the aseptic filter 104, however, if no filter 104 or similar deviceis needed, the second end of the first portion 108 can be coupleddirectly to or integrally formed with a second portion 116 of theassembly 100. The second portion 116 corresponds to the conduit 20 b,including the portion of the conduit that is received within the tube 24of the flow meter 14. The construction of the second portion 116 isgenerally the same as described above with respect to FIG. 3, althoughthe length and configuration of the second portion 116 can varydepending on the specific filling system used. The end of the secondportion 116 opposite the first portion 108 is coupled directly to orintegrally formed with a third portion 120 corresponding to the conduits20 c and 20 d. The length of the third portion 120 can be varied asneeded. A nozzle 124 is coupled to an end of the third portion 120, anda removable nozzle cap 128 can be placed on the nozzle 124 until thefill line assembly 100 is installed and ready for use in the fillingsystem 10.

The portions 108, 116, and 120 of the fill line assembly can be made ofthe same materials and in the same manners as discussed above, and inthe illustrated embodiment are made of C-FLEX tubing. The nozzle 124,caps 112 and 128, and the filter 104 can also be made from plastics orother materials suitable for use in sterile environments. The entirefill line assembly 100 can be packaged in a single package, and if thefill line assembly 100 is to be used in a sterile application, theentire package can be sterilized via an irradiation process, an ethyleneoxide treatment, or other suitable sterilization techniques. The fillline assembly 100 could be used once, disposed of, and then a new,sterilized fill line assembly 100 could be inserted for use in thefilling system 10, thereby eliminating the need for CIP or SIP processesand validation processes.

The components of the fill line assembly 100 are sized and configured topermit insertion into the components of the filling system 10. Forexample, at least a portion of the fill line assembly 100 is sized topass through the stop valve 16, while the same or another portion of thefill line assembly 100 is sized to pass through the tube 24. Similarmethods as those described above can be used to facilitate inserting thefill line assembly 100 into filling system 10. If no filter 104 isincorporated into the fill line assembly 100, at least one of the nozzle124, the cap 128, and the cap 112 can be sized and configured to permitpassage through the tube 24 and the stop valve 16. Achieving the properpositioning of the second portion 116 within the tube 24 can occur insubstantially the same manner as discussed above with respect topositioning the conduit 20 b inside the tube 24.

It is to be understood that the disposable fill line assembly 100 can beused with, or modified to be used with, other filling systems that maynot utilize a flow meter, but rather that incorporate other fluidhandling devices. As used herein and in any appended claims, the term“fluid handling device” means a device associated with a fluid handlingsystem and through which the fluid pathway passes, regardless of whetherthe fluid handling device acts on the fluid and/or fluid pathway, orpassively monitors or analyzes the fluid and/or the fluid pathway. Forexample, some known filling systems utilize peristaltic pumps or otherfluid handling devices for filling containers (e.g., bags) with thedesired fluid in the filling system. In such an application, thedisposable fill line assembly 100 can be used to reduce or eliminate theneed for cleaning and validating the components of the disposable fillline assembly 100. Any desired number of conduit portions and any otherdesired components can be used and interconnected as needed depending onthe particular filling system. Preferably, a fill line assembly designedfor use in a specific filling system will be pre-sterilized and packagedto be used as a single-use, disposable fill line assembly. Byincorporating a disposable nozzle 124 into the disposable fill line, inplace of a metal nozzle that must be cleaned and validated betweenbatches, the time and cost associated with changing batches can begreatly reduced.

FIGS. 16-24 a illustrate yet another filling system using a secondembodiment of a disposable fill line 300. Like parts of the fillingsystem have been given like reference numerals. Referring to FIG. 18,the portion of the disposable fill line 300 defining the conduit portion20 b includes first and second tube liner inserts 304 a, 304 b and aliner 308. The tube liner inserts 304 a, 304 b are secured to oppositeends of the liner 308 using any suitable thermal, RF, or adhesivebonding techniques or other suitable coupling techniques, such that afluid flow path is defined through the tube liner inserts 304 a, 304 band the liner 308. In the illustrated embodiment, the ends of the tubeliner inserts 304 not coupled to the liner 308 include areduced-diameter connection tip 312 that can be configured with a barb316 or in other suitable manners to facilitate connection of the tubeliner inserts 304 to the other conduit portions 20 a, 20 c of thedisposable fill line 300. Additionally, the conduit portions 20 a, 20 ccan further be bonded or otherwise secured to the respective connectiontips 312 using any suitable thermal, RF, or adhesive bonding techniques.As shown in FIGS. 16, 17 and 18, the disposable fill line 300 alsoincludes a plastic nozzle 320 connected to the conduit portion 20 c.While not shown, the disposable fill line 300 can also include end capsthat cover the nozzle 320 and the free end of the conduit portion 20 a,as described above with respect to the disposable fill line 100.

In a similar manner as described above with respect to fill line 100,the conduit portions 20 a, 20 c, and the liner 308 of the disposablefill line 300 can be made from C-FLEX tubing or other suitablematerials. The tube liner inserts 304 a, 304 b and the nozzle 320 canalso be made from C-FLEX tubing or other suitable plastics, but in theillustrated embodiment are more rigid than the conduit portions 20 a, 20c and the liner 308.

Like the fill line 100 discussed above, the entire fill line 300 can bepre-assembled and packaged in a single package, and if the fill line 300is to be used in a sterile application, the entire package can besterilized via an irradiation process, an ethylene oxide treatment, orother suitable sterilization techniques. The fill line 300 could be usedonce, disposed of, and then a new, sterilized fill line assembly 300could be inserted for use in the filling system, thereby eliminating theneed for CIP or SIP processes and validation processes.

To accommodate and position the disposable fill line 300 with respect tothe flow meter 14, the filling system includes first and second end capfixtures 324 a, 324 b (best shown in FIGS. 16 and 17). The end capfixtures 324 a, 324 b are substantially identical, and each includes aflange 328 configured to engage with the corresponding flange 160 a, 160b on the upper or lower end of the cylinder 22. A gasket or seal ringcan be positioned between the flange 328 and the corresponding flange160 a, 160 b if desired. Each end cap fixture 324 a, 324 b furtherincludes a tubular body portion 332 extending from the flange 328. Thetubular body portion 332 includes a slot or groove 336, the purpose ofwhich will be described in detail below. The illustrated end capfixtures 324 a, 324 b are made of metal (e.g., stainless steel),however, they could alternatively be made of a suitable plasticmaterial.

FIGS. 19 and 20 illustrate the end cap fixtures 324 a, 324 b secured tothe respective flanges 160 a, 160 b by clamps 165 a, 165 b. Next, thepre-assembled disposable fill line 300 can be inserted into the bodyportion 332 of the upper end cap fixture 324 a, beginning with thenozzle 320, and is fed through the flow meter 14 in a manner similar tothat discussed above (e.g., using a rod or other suitable insertionaid), until the liner 308 is positioned in the tube 24 between the upperand lower end cap fixtures 324 a, 324 b. Those skilled in the art willalso understand that the fill line 300 could alternatively be insertedfrom the bottom of the flow meter 14 in an upward direction.Furthermore, if the fill line is not completely pre-assembled,installation of the tube liner inserts 304 a, 304 b and the liner 308can take place prior to connecting the conduit portions 20 a, 20 c.

With reference to FIG. 21, the upper tube liner insert 304 a ispositioned with respect to the upper end cap fixture 324 a such that agroove or slot 340 (see FIG. 18) formed in the tube liner insert 304 ais aligned with the groove 336 in the body portion 332 of the upper endcap fixture 324 a. A hairpin clip 344 a or other suitable securingdevice can be positioned in the groove 336 and the slot 340 to retainthe tube liner insert 304 a in position (e.g., axially and rotationally)relative to the upper end cap fixture 324 a.

Once the upper tube liner insert 304 a is secured relative to the flowmeter 14, the lower tube liner insert 304 b is positioned with respectto the lower end cap fixture 324 b both axially and rotationally. In theillustrated embodiment, the lower tube liner insert 304 b can be pulledaxially, thereby stretching the liner 308 somewhat, until the slot 340in the lower tube liner insert 304 b is aligned with the groove 336 inthe lower end cap fixture 324 b. With reference to FIG. 22, an alignmentmark or indicia 348 (see also FIG. 18) formed on the reduced diametertip 312 (and visible through the connected translucent conduit 20 c) orelsewhere on the lower tube liner insert 304 b can be rotationallyaligned with a similar alignment mark or indicia 348 on the upper tubeliner insert 304 a (see FIG. 21) to ensure that the liner 308 is nottwisted inside the tube 24. The alignment marks 348 can be printed onthe tube liner inserts 304 a, 304 b, can be machined or otherwise formedthereon as projections, detents, ribs or grooves, or can be otherwisesuitably attached or provided. Once the lower tube liner insert 304 b isaxially and rotationally aligned, a hairpin clip 344 b or other suitablesecuring device is positioned in the groove 336 and the slot 340 toretain the tube liner insert 304 b in position (e.g., axially androtationally) relative to the lower end cap fixture 324 b.

Once the fill line 300 is inserted into the flow meter 14, the fillsystem can be started and operated in much the same manner as previouslydiscussed above. Note, however, that in the embodiment of FIGS. 16-24 a,the purging or evacuation of gas (e.g., air) trapped between the outersurface of the liner 308 and the inner wall of the tube 24 occurs in aslightly different manner. With reference to FIG. 23, air is purged frombetween the liner 308 and the tube 24 by allowing the air to traveltoward a respective end cap fixture 324 a, 324 b, between an outersurface of the respective tube liner insert 304 a, 304 b and the innersurface of the respective body portion 332, and out of the groove 336formed in each end cap fixture 324 a, 324 b (as represented by thearrows A in FIG. 23). Additionally, or alternatively, the embodiment ofFIGS. 16-24 a could also be modified to include a vacuum assemblysimilar to the vacuum assemblies 179, 245 discussed above to furtherfacilitate purging gas from between the liner 308 and the tube 24.

Those skilled in the art will understand that changes to the embodimentof FIGS. 16-24 a can be made without departing from the scope of theinvention. For example, FIG. 24 b illustrates an alternative option forsecuring the fill line 300 with respect to the flow meter 14. In theembodiment of FIG. 24 b, an end cap fixture 350 is illustrated and isgenerally similar in shape to the flanges 328 of the end cap fixtures324 a, 324 b, but does not include a tubular body portion extendingtherefrom. A substantially C-shaped clip 354 made of plastic or othersuitable materials is used to secure the respective tube liner inserts304 a, 304 b in position with respect to the flanges 160 a, 160 b of theflow meter 14 by sliding the C-shaped clip 354 around the slot 340 ofthe tube liner inserts 304 a, 304 b. The slot 340 may need to bere-sized in order to fit properly within the C-shaped clip 354. Once theclip 354 is positioned around the slot 340 in the tube liner insert 304a, 304 b and rests on the respective flange 160 a, 160 b, the end capfixture 350 can be placed over the clip 354 on the respective flange 160a, 160 b and clamped with clamps 165 a, 165 b to secure the assembly.The tube liner inserts 304 a, 304 b extend through an aperture 358 inthe respective end cap fixture 350 for connection to the respectiveconduit 20 a, 20 c.

While various embodiments of the invention are illustrated anddescribed, each provides a liner for a flow meter that can be positionedin the tube of the flow meter and removably coupled with the tube suchthat fluid flowing through the tube flows through the liner withoutcontacting an inner surface of the tube. After use, the liner can beremoved from the tube without requiring substantial disassembly of theflow meter and without requiring the removal of the tube from within theflow meter. The liner does not permanently modify or affect the tube,and therefore, the flow meter remains operable both with a linerinstalled and without a liner installed. The liner provides acost-effective alternative to the CIP/SIP and validation processescommonly required for pharmaceutical applications utilizing a flowmeter. Additionally, the liner can provide a cost-effective manner ofprotecting the tube of the flow meter in applications involving causticand/or corrosive materials.

The foregoing description of the present invention has been presentedfor purposes of illustration and description. Furthermore, thedescription is not intended to limit the invention to the form disclosedherein. Consequently, variations and modifications commensurate with theabove teachings, and the skill or knowledge of the relevant art, arewithin the scope of the present invention. The embodiments describedherein are further intended to explain best modes known for practicingthe invention and to enable others skilled in the art to utilize theinvention in such, or other, embodiments and with various modificationsrequired by the particular applications or uses of the presentinvention. It is intended that the appended claims be construed toinclude alternative embodiments to the extent permitted by the priorart.

Various features of the invention are set forth in the following claims.

1. A flow meter assembly comprising: a flow meter including a tubethrough which a fluid flows, the flow meter being operable to measurethe amount of fluid flowing through the tube; and a liner positionedwithin the tube, the liner being removably coupled with the flow metersuch that fluid flowing through the tube flows through the liner withoutcontacting an inner surface of the tube.
 2. The flow meter assembly ofclaim 1, wherein the liner is made of a flexible plastic tubing.
 3. Theflow meter assembly of claim 2, wherein the liner is made of athermoplastic elastomer tubing.
 4. The flow meter assembly of claim 1,wherein the flow meter is operable to measure fluid flowing through thetube both when the liner is coupled with the tube and when the liner isremoved from the tube.
 5. The flow meter assembly of claim 1, whereinthe liner is in close contact with the inner surface of the tube suchthat substantially no gases are trapped between the liner and the innersurface of the tube.
 6. The flow meter assembly of claim 5, furthercomprising a purging device configured to remove gases trapped betweenthe liner and the inner surface of the tube.
 7. The flow meter assemblyof claim 6, wherein the purging device is a vacuum assembly.
 8. The flowmeter assembly of claim 5, wherein the liner is expanded into engagementwith the inner surface of the tube by the fluid passing through theliner.
 9. The flow meter assembly of claim 1, wherein the liner isremovably coupled to the tube without the use of any mechanical bondingbetween the liner and the inner surface of the tube.
 10. The flow meterassembly of claim 1, wherein the liner is removably disposed within thetube without removing the tube from the flow meter.
 11. The flow meterassembly of claim 1, wherein the liner is part of a fill line thatdefines a fluid flow pathway from a fluid supply, through the flowmeter, and to a fluid discharge nozzle.
 12. The flow meter assembly ofclaim 11, wherein the fluid discharge nozzle is part of the fill line.13. The flow meter assembly of claim 11, wherein the entire fill line ismade of plastic.
 14. The flow meter assembly of claim 11, wherein thefill line is a sterilized fill line.
 15. The flow meter assembly ofclaim 11, wherein the fill line includes a first tube liner insertcoupled with an inlet end of the liner and a second tube liner insertcoupled with an outlet end of the liner, each of the tube liner insertsconfigured to receive a securing device for securing the liner withinthe tube.
 16. The flow meter assembly of claim 15, wherein the tubeliner inserts are more rigid than the liner.
 17. The flow meter assemblyof claim 1, wherein the liner is a sterilized liner.
 18. The flow meterassembly of claim 1, wherein the flow meter is a Coriolis type flowmeter.
 19. The flow meter assembly of claim 1, wherein the liner isremovably coupled with the tube.
 20. A method of operating a flow meterassembly including a flow meter having a tube through which a fluidflows, the flow meter being operable to measure the amount of fluidflowing through the tube, and a liner configured to be positioned withinthe tube, the method comprising: inserting the liner into the tube;passing a fluid through the tube such that the fluid flows through theliner without contacting an inner surface of the tube; and after passingthe fluid through the tube, removing the liner from the tube.
 21. Themethod of claim 20, further comprising: evacuating gas from between theinserted liner and the inner surface of the tube.
 22. The method ofclaim 21, wherein a purging device is used to evacuate the gas frombetween the inserted liner and the inner surface of the tube.
 23. Themethod of claim 22, wherein the purging device is a vacuum assembly. 24.The method of claim 21, wherein evacuating gas from between the insertedliner and the inner surface of the tube is achieved by passing a fluidthrough the liner to expand the liner into engagement with the innersurface of the tube.
 25. The method of claim 20, wherein inserting theliner into the tube is accomplished without mechanically bonding theliner to the tube.
 26. The method of claim 20, wherein removing theliner from the tube is done without removing the tube from the flowmeter.
 27. The method of claim 20, wherein inserting the liner into thetube is done without removing the tube from the flow meter.
 28. Themethod of claim 20, further comprising: after removing the liner fromthe tube, inserting a second liner into the tube; and passing a fluidthrough the tube such that the fluid flows through the second linerwithout contacting the inner surface of the tube.
 29. The method ofclaim 28, wherein no cleaning fluid is passed through the tube afterremoving the liner from the tube and before inserting the second linerinto the tube.
 30. The method of claim 28, wherein the fluid flowingthrough the first liner is different from the fluid flowing through thesecond liner.
 31. The method of claim 20, wherein the liner issterilized prior to being inserted into the tube.
 32. The method ofclaim 20, wherein inserting the liner into the tube includes securingthe liner with respect to the flow meter by coupling the liner to theflow meter at a location spaced from the tube.
 33. The method of claim20, wherein fluid flowing through the liner expands the liner intoengagement with an inner surface of the tube.
 34. The method of claim20, wherein inserting the liner into the tube includes rotationallyaligning the portions of the liner at opposite ends of the tube toensure that the liner is not substantially twisted within the tube. 35.The method of claim 20, wherein the liner is part of a fill line thatdefines a fluid flow pathway from a fluid supply, through the flowmeter, and to a fluid discharge nozzle, and wherein fluid flows from thefluid supply, through the flow meter, and to the fluid discharge nozzlethrough the fill line.
 36. The method of claim 35, wherein the fill lineincludes the fluid discharge nozzle and wherein inserting the liner intothe tube includes first passing the fluid discharge nozzle through thetube.
 37. The method of claim 35, wherein the liner portion of the fillline includes a liner conduit connected between two tube liner inserts,and wherein inserting the liner into the tube includes positioning theliner conduit and at least a portion of each tube liner insert withinthe tube.
 38. The method of claim 35, wherein the liner portion of thefill line includes a liner conduit connected between two tube linerinserts, and wherein inserting the liner into the tube includesreleasably securing the two tube liner inserts with respect to the flowmeter at locations spaced from the tube.
 39. The method of claim 35,wherein the entire fill line is sterilized prior to being inserted intothe tube.
 40. A fill line for a fluid handling system operable todispense fluid from a fluid supply through a fluid handling device, thefill line comprising: a first portion in fluid communication with thefluid supply and located upstream of the fluid handling device; a secondportion removably positioned within and extending through an enclosedportion of the fluid handling device; and a third portion locateddownstream of the fluid handling device.
 41. The fill line of claim 40,wherein the first, second, and third portions include plastic tubing.42. The fill line of claim 41, wherein the plastic tubing is sterilized.43. The fill line of claim 41, wherein the plastic tubing is not uniformover the length of the fill line.
 44. The fill line of claim 41, whereinthe plastic tubing includes thermoplastic elastomer tubing.
 45. The fillline of claim 40, wherein the fill line further includes a fluiddischarge nozzle coupled with the third portion.
 46. The fill line ofclaim 45, wherein the fill line further includes a removable cap placedon the fluid discharge nozzle prior to the second portion beingremovably positioned within the fluid handling device.
 47. The fill lineof claim 45, wherein the discharge nozzle is sized to be passed throughthe enclosed portion of the fluid handling device.
 48. The fill line ofclaim 40, wherein the fluid handling device is a flow meter.
 49. Thefill line of claim 48, wherein the flow meter is a Coriolis type flowmeter.
 50. The fill line of claim 40, wherein the second portionincludes a first tube liner insert, a second tube liner insert, and aliner conduit coupled between the first and second tube liner inserts.51. The fill line of claim 50, wherein the liner conduit is less rigidthan the tube liner inserts.
 52. The fill line of claim 40, wherein thesecond portion is removably positioned within a tube in the fluidhandling device.
 53. The fill line of claim 52, wherein the secondportion lines the inner surface of the tube such that a fluid passingthrough the fluid handling device flows through the second portionwithout contacting an inner surface of the tube.
 54. The fill line ofclaim 52, wherein the second portion is removably positioned within thetube without any mechanical bonding between the second portion and aninner surface of the tube.